1. Field of the Invention
The invention relates to a dummy plug.
2. Description of the Related Art
Japanese Unexamined Patent Publication No. 2008-305660 discloses a connector that includes a housing formed with a plurality of terminal accommodating chambers. A one-piece rubber plug is mounted in a rear end portion of the housing and includes a plurality of seal holes corresponding to the terminal accommodating chamber. A holder is arranged behind the one-piece rubber plug and includes a plurality of through holes corresponding to the seal holes. Terminal fittings are inserted through the through holes and the seal holes and into the terminal accommodating chambers.
A dummy plug is mounted in the connector. The dummy plug is long and narrow in forward and backward directions and formed. A waterproof portion is formed at a front end portion of the dummy plug and a plate-like operating portion extends back from the rear end of the waterproof portion. The operating portion can be grasped to pull the dummy plug out. Two resilient locking pieces extend backward from a front part of the operating portion and are supported on one end.
The waterproof portion penetrates through the seal hole of the one-piece rubber plug to close the seal hole in a liquid-tight manner when the dummy plug is mounted into the connector. Further, the operating portion penetrates through the through hole of the holder and the resilient locking pieces engage an edge region of the through hole on the front surface of the holder. This engagement of the resilient locking pieces and the holder holds dummy plug in a retained state.
The resilient locking pieces of the dummy plug are supported on one end. As a result, there is a problem that deformation rigidity is relatively low and engaging forces of retaining portions and the resilient locking pieces are weak. Further, the two resilient locking pieces are arranged at opposite sides of the operating portion. As a result, the resilient locking pieces are deformed resiliently in directions toward the outer surfaces of the operating portion when the operating portion and the resilient locking pieces pass through the through hole. The opening dimension of the through hole is set. Thus, a deformation margin of the resilient locking pieces is limited to a dimension obtained by subtracting the thickness of the operating portion and thicknesses of the resilient locking pieces from the opening dimension of the through hole and it is difficult to ensure a sufficiently large deformation margin. The deformation margin of the resilient locking pieces is an engagement margin of the resilient locking pieces and the holder. Accordingly, the reliability of a retaining function of the dummy plug is problematically low.
The invention was completed based on the above situation and an object thereof is to improve the reliability of a retaining function.